This invention is related to the field of organometal catalyst compositions.
The production of polymers is a multi-billion dollar business. This business produces billions of pounds of polymers each year. Millions of dollars have been spent on developing technologies that can add value to this business.
One of these technologies is called metallocene catalyst technology. Metallocene catalysts have been known since about 1958. However, their low productivity did not allow them to be commercialized. About 1974, it was discovered that contacting one part water with one part trimethylaluminum to form methyl aluminoxane, and then contacting such methyl aluminoxane with a metallocene compound, formed a metallocene catalyst that had greater activity. However, it was soon realized that large amounts of expensive methyl aluminoxane were needed to form an active metallocene catalyst. This has been a significant impediment to the commercialization of metallocene catalysts.
Fluoro-organo borate compounds have been use in place of large amounts of methyl aluminoxane. However, this is not satisfactory, since such borate compounds are very sensitive to poisons and decomposition, and can also be very expensive.
Clays having a lamellar structure have also been used to activate metallocenes, however, activity has not been high in the absence of cation exchanging or pillaring agents. Pillaring occurs when cations between the layers are replaced by other cations, usually more bulky and sometimes organic cations, that are called pillars due to their role of propping open the microscopic sheets and thus slightly expanding the layered structure of the clay to slightly increase its porosity. Clay also tends to be fine and dusty making it difficult to handle commercially in polymerization processes.
It should also be noted that having a heterogeneous catalyst is important. This is because heterogeneous catalysts are required for most modem commercial polymerization processes. Furthermore, heterogeneous catalysts can lead to the formation of substantially uniform polymer particles that have a high bulk density. These types of substantially uniform particles are desirable because they improve the efficiency of polymer production and transportation. Efforts have been made to produce heterogeneous metallocene catalysts; however, these catalysts have not been entirely satisfactory.
An object of this invention is to provide a process for producing a new type of high porosity, amorphous, oxide matrix composition comprising residual elements of a layered mineral and an oxide compound precursor. This oxide matrix composition can be utilized as an activator for metallocenes.
Another object of this invention is to provide the novel oxide matrix composition.
Another object of this invention is to provide a process that produces a catalyst composition that can be used to polymerize at least one monomer to produce a polymer.
Another object of this invention is to provide the catalyst composition.
Yet another object of this invention is to provide a process comprising contacting at least one monomer and the catalyst composition under polymerization conditions to produce the polymer.
Still another object of this invention is to provide an article that comprises the polymer produced with the catalyst composition of this invention.
In accordance with an embodiment of this invention, a process is provided to produce an oxide matrix composition. The process comprises (or optionally, xe2x80x9cconsists essentially of,xe2x80x9d or xe2x80x9cconsists ofxe2x80x9d):
1) substantially decomposing or exfoliating at least one layered mineral to produce residual mineral components;
wherein the layered mineral is a clay, clay mineral, or other ion exchanging compound having a layered crystal structure;
2) contacting the residual mineral components and at least one oxide compound precursor to produce a first mixture;
wherein the oxide compound precursor is selected from the group consisting of a silica source, alumina source, aluminosilicate source, aluminophosphate source, or combinations thereof.
3) subjecting the first mixture to such conditions to form a gel or precipitate; and
4) calcining the gel or precipitate at a temperature in the range of about 150xc2x0 C. to about 800xc2x0 C. to produce the oxide matrix composition.
In accordance with another embodiment of this invention, the oxide matrix composition is provided. The novel matrix oxide composition constitutes a previously unknown type of oxide matrix composition comprising residual mineral components and an oxide precursor compound. The oxide matrix composition has a high porosity and an amorphous structure, which is unlike that of previously known oxides and minerals.
In accordance with another embodiment of this invention, a process to produce a catalyst composition is provided. The process comprises contacting an organometal compound, an organoaluminum compound, and an oxide matrix composition to produce the catalyst composition,
wherein the organometal compound has the following general formula:
(X1)(X2)(X3)(X4)M1
wherein M1 is selected from the group consisting of titanium, zirconium, and hafnium;
wherein (X1) is independently selected from the group consisting of cyclopentadienyls, indenyls, fluorenyls, substituted cyclopentadienyls, substituted indenyls, and substituted fluorenyls;
wherein substituents on the substituted cyclopentadienyls, substituted indenyls, and substituted fluorenyls of (X1) are selected from the group consisting of aliphatic groups, cyclic groups, combinations of aliphatic and cyclic groups, silyl groups, alkyl halide groups, halides, organometallic groups, phosphorus groups, nitrogen groups, silicon, phosphorus, boron, germanium, and hydrogen;
wherein at least one substituent on (X1) can be a bridging group which connects (X1) and (X2);
wherein (X3) and (X4) are independently selected from the group consisting of halides, aliphatic groups, substituted aliphatic groups, cyclic groups, substituted cyclic groups, combinations of aliphatic groups and cyclic groups, combinations of substituted aliphatic groups and cyclic groups, combinations of aliphatic groups and substituted cyclic groups, combinations of substituted aliphatic groups and substituted cyclic groups, amido groups, substituted amido groups, phosphido groups, substituted phosphido groups, alkyloxide groups, substituted alkyloxide groups, aryloxide groups, substituted aryloxide groups, organometallic groups, and substituted organometallic groups;
wherein (X2) is selected from the group consisting of cyclopentadienyls, indenyls, fluorenyls, substituted cyclopentadienyls, substituted indenyls, substituted fluorenyls, halides, aliphatic groups, substituted aliphatic groups, cyclic groups, substituted cyclic groups, combinations of aliphatic groups and cyclic groups, combinations of substituted aliphatic groups and cyclic groups, combinations of aliphatic groups and substituted cyclic groups, combinations of substituted aliphatic groups and substituted cyclic groups, amido groups, substituted amido groups, phosphido groups, substituted phosphido groups, alkyloxide groups, substituted alkyloxide groups, aryloxide groups, substituted aryloxide groups, organometallic groups, and substituted organometallic groups;
wherein substituents on (X2) are selected from the group consisting of aliphatic groups, cyclic groups, combinations of aliphatic groups and cyclic groups, silyl groups, alkyl halide groups, halides, organometallic groups, phosphorus groups, nitrogen groups, silicon, phosphorus, boron, germanium, and hydrogen;
wherein at least one substituent on (X2) can be a bridging group which connects (X1) and (X2);
wherein the organoaluminum compound has the following general formula:
Al(X5)n(X6)3xe2x88x92n
wherein (X5) is a hydrocarbyl having from 1 to about 20 carbon atoms;
wherein (X6) is a halide, hydride, or alkoxide; and
wherein xe2x80x9cnxe2x80x9d is a number from 1 to 3 inclusive.
In accordance with still another embodiment of this invention, a process is provided comprising contacting at least one monomer and the catalyst composition under polymerization conditions to produce a polymer.
In accordance with yet another embodiment of this invention, an article is provided. The article comprises the polymer produced in accordance with this invention.
These objects, and other objects, will become more apparent to those with ordinary skill in the art after reading this disclosure.